1. Field of the Invention
The present invention relates to a technology for cooling a continuously variable transmission in a straddle-type vehicle such as a motorcycle.
2. Description of Related Art
A straddle-type vehicle in which a belt-type continuously variable transmission and an engine are both arranged forward of a rear wheel has been proposed, for example, in Japanese Unexamined Patent Publication No. 2002-19669. In the continuously variable transmission of Japanese Unexamined Patent Publication No. 2002-19669, the spacing between a driving side pulley and a driven side pulley is small and hence it is difficult to lower the temperature of a belt looped around the driving and driven side pulleys. For this reason, outside air is introduced into a case for housing the continuously variable transmission.
However, in the straddle-type vehicle of Japanese Unexamined Patent Publication No. 2002-19669, an air exhaust passage is extended downward along a side of the case, so that air warmed in the case is exhausted downward. Thus, excellent heat exhaust efficiency is not acquired.